Combination drafting instrument.



W. SMITH. communion DBAFTING INSTBUMENT.

APPLICATION FILED SEPT. 22, 1909.

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In ven for.

Patented Oct. 18,1910.

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UNITED. s'rArps PATENT OFFICE.

WILLIAM SMITH, or' PORTLAND, OREGON.

' 'Toallwhom'itmyconcemi draftsm'ans service, it will be found espe-- Be itknown that I, WILLIAM- SMITH, a citizen of the United States, residing at the city of'Port-land, in the county of-Multnomah and State of Oregon, have invented certain new and useful Improvements in Combination Drafting Instruments, of

which the following is a specification.

This invention relates to that class of mathematical instruments in which two or more members are conjoined for the purposes of drawing predetermined, or experimental lines, or diagrams, according to measuremen t,and the object of my invention is .to produce, iii simple, cheap and efii cient'form, a combination drawing and measulliing instrument, or tool, which shall embody a t for use in delineating geometrical work, and while designed to be sufiiciently accurate in construction and operation for any regular cially valuable for beginners, students and school attendants generally, as a practical.

means of education in measurements, lines, an 1% and circles, as wellashandy asa plain ruFer, measure and scale for any purpose.

Briefly speaking, my invention embodies in one instrument three main members, viz: a ruler, graduated or scaled to inches and fractions thereof,-a protractor, divided into degrees and fractions of the circle,and

' a slide adapted to, be removably-fitted with a pencil or stylus for serving as a comfpass in drawing circles and lines radiating rom the center of the protractor,-these three members being permanently or adjustably.

connected -together,all as will more fully appear by the following detailedvdescription an by r reference to the accompanying drawing forming part of this specification. In the drawing, similar letters of refer- I ence indicate like parts in the several figures.

Figure 1 is a p the simpler forms of my instrument. F1 2 is a cross section on line 2, 2, Fig. 1.

4 is a plan of a. modification of my inven-' tion, Fig. 5 is a lan of part of the iruler, showing a 'modi ed construction thereof, and of the slide. Fig. 6 is a cross section on line 6, 6, Fig. 5'.

A is a flat rule, graduated, by preference,-

into inches and fractions thereof, along one to serve as a measure,and to inches,

comnma'rion nnarrme msraumn'nr.

e instrumentalities ordinarily required an or face view of one of ig.. 3 is a similar section on line 3, 3, Fig. 1. Fig.

Patented Oct. 18, 1910. Serial No. 519,078.

vide a handy scale for use of the draftsman in contingencies where same may be required.

a is a slot extending centrally of and parallel with the edges just named, and preferably open at the outward extremity. This slot is discontinued so as to leave a solid portion of the rule toward its inner end where it is pivoted to the center of a protractor B, beyond which pivot point the rule terminates in a finger or indicating pointer a the point of which is in alinement with the center of the slot (1', in Fig. 1, and with the left-hand edge of the rule A in the modification shown in Fig. 4.

its pointer .or finger a is superposed upon the protractor B, and I have shown asimpl'e As seen in all the figures, the rule A with form of. pivotin the shape of a hollow rivet b, it beingintended thataneedle point (such as commonly used in drawing tools) shall be passed downthrough the central aperture B and into the paper or board being drawn upon. This rivet b is preferably countersunk into the lower .face of the hub of the protractor so that it may lie level.

b 6 represent a plurality of extra holes through which extra needles may be passed to assist-in steadying the work at any point as will be readily appreciated.

' The protractor B is divided and graduated into degrees of the circle, and preferably also into minutes and seconds. I C is a slide, or cross head, superposed upon the rule A, perforated at its center,

. and preferably provided with a hollow rivet,

or thimble C, will slide along A, overlapping the slot a therein, so as to retainv the slide C inoperative position.

the under flange of which .The' hollow-center or aperture C of this rivet-or thimble is of such a diameter as will a pencil, pointed lead, stylus or ruling according to requirements,'and I rovi e a set 'screw{? passing transversely t rough a proper way invthe slide and thimblefor sethe under side of the rule adapt it to receive a marking device such as en,

curlng such marking device when same has been set and is to .be operated. Another pointed set screw 0. passes vertically through the slide C at one side thereof and impinges u on the surface of the rule, to hold the s ide and its marking device at any fixed point. 0 0 are fingers projecting from the sides. of the slide C so as to register with any predetermined point on the. rule. or

scale.

In the modification shown in Fig. 4, the rule A is offset from the protractor B, the left-handedge of said rule being alined with the center of the protractor and consequently with the needlepoint when inserted in the aperture 13; the same style of indicating finger a. as in Fig. 1, being used,

' but projecting from a specially formed hub B so as also to be in line with the edge of the rule just named. This arrangement willsuit some purposes better than the former style described as for Fig. 1, as lines can thus be drawn outward by a separate pencil or pen, from the periphery of the protra'ctor B along'the clearly-exposed edge ofthe rule -A, (instead of havingto be'mad'e inside the slot a,) in all cases where accuracy is desired in the use of the combined rule; comass and protractor. The rule A, of course, is intended to be used, if desired, simply as a ruler and measure. In Fig. 4 I have shown a detachable cap D at the outer end of the rule A. This cap may be used, if. de-

sired, to store "extra needles, leads, etc., as

well as to prevent the slide C from passing out of the slot at and thus being, perhaps inislaid when the instrument is'out of use.

In the modification, Figs. 5 and 6, I have made the body of the rule A, and also the slide C, with 'rai sed central portions, A and v C, respectively, which enables the lower end of the rivet C to beconveniently countersunk, and tendsto stifi'en the rule as well.

"All other; parts of the device will remain the same.

' The operations the different parts of my improved instrument, as well as those of the component members when used in combination will be so well understood from the-foregoing, and from the drawing, as not to hererequire further explanation. I

may say, however, that I do not limit my-.

self to any of the precise details of construction as to pivot points, contours of parts, graduations of rules and scales, or any other specifically described feature, as these may all be var1ed or modified according to judgment, or special requirements, without departing from the principle or sacrificing the advantages of my invention. And furthermore, I may employ steel, brass, nickel, aluminum, or any other metal or metals, or

alloys,-or gutta percha, celluloid, wood,

or other material or compound, 'without I 1 prejudice to the article in vmanufacturing the same.

What I claim and desire 'to-secureby Letters Patent is as follows:

*1. A combination drafting instrument, composed, essentially, of the following instrumentalities, viz :agraduated rule having straight edges for the greater, portion of its length, a longitudinal slot parallel to and between such edges, and an ndicating finger projecting from its inner end,-a pro-.

tractor upon which said rule is superposed insuch manner that said finger may register with any point on the rim of said protractor,a hollow rivet serving as a central pivot for said protractor, as a means of connection thereof with. said rule, and also adapted to receive a needle point,and a slidemovable' in the slot in the rule and having a pointer at its side adapted to register with any point on the ru1e,and a central aperture for the reception of a marking device,-all substantially as and for the purposes set forth.

2. A combination drafting instrument, composed, essentially, of the following instrumentalities, viz: a graduated rule hav ing straight edges for the greater portion of its length, a longitudinal slot parallel to and between such edges, and an ndicating finger projecting from its inner end,a protractor upon which said rule is superposed in such manner that one edge of said rule is in direct alinement with the center of said protractor, and-also so that said finger may register with any point on the rim of said protractor,a hollow rivetserving as a central pivot for said protractor, as a means of connection thereof with said rule, and also adapted to receive a needle point,-and'a slide movable in the slot in the rule and having a pointer at its side adapted to register with any point on the rule, and a central aperture for the rece tion of a marking (18? vice,all substantially as and for the purposes set forth. t

Signed at the city of Salem, State of Oregon, this 30th day of July, 1909.

- WILLIAM SMITH.

Witnesses: G. W; JAMES, GEORGE TAZWELL. 

